The paper shows the efficiency of electromembrane treatment of semi-products of sugar production in order to increase the yield of sugar by reducing its losses in molasses. Based on the analysis of changes in the studied parameters of semiproducts of sugar production during the electrodialysis process, scientific data were obtained on the effect of electromembrane treatment on the chemical composition and technological quality of purified semiproducts of sugar production, as well as on decrease in calcium salts content in them. The purpose of the research is to create a highly efficient method for production of white sugar, allowing to increase the yield of sugar from raw materials and reduce the amount of excipients by means of electrodialysis with its subsequent practical implementation at industry enterprises. Under production conditions, it was found that electromembrane treatment of one batch (7 t) of purified juice allows to additionally obtain up to 35 kg of sugar, a batch of syrup – up to 130 kg, and soft sugar effluent of II crystallization – up to 255 kg. Electromembrane treatment of molasses makes it possible to: reduce the mass fraction of calcium salts to dry matters by 39 % of their initial content; increase molasses purity by 8.5 %; reduce the molasses-forming coefficient by 21 % by reducing the content of potassium and sodium. In this case, the estimated amount of additional sugar obtained from it will make 5.1 % by weight or 392.7 kg of sugar from one batch of processed molasses. The research will allow to develop scientific and technological aspects of purification of semi-products of sugar production using electromembrane treatment.